Fracture

Bought a 99 WJ 4.7 4x4 this past week and found out the previous owner did the ol' "pull the CEL bulb" from the cluster and didn't find out until later on.

Anyways..

I also am having an issue with the reverse lights not coming on in reverse. However the transmission shifts fine in all gears. Wondering if the reverse lights may have something to do with the P1698 which I read is some issue regarding communication with the PCM. I've also read that WJs don't have TCMs but this code can mean communication between PCM and transmission control?

I've tried researching this as much as I can, and it seems that people have said it usually means a bad PCM. Before I drop $200+ on a new one, doesn't it have to be paired/flashed to the security or key so it will actually start the Jeep?

dave1123

Neutral Safety Switch 42re trans

Okay, the reverse lights are switched on by the Neutral Safety switch with a single wire. You may have a broken wire in the plug itself. Mine had exactly that. If you need a new plug, they are available thru a dealer, although they may have to be ordered.

The P1698 code is a loss of communication between the PCM and the transmission control. This might also be a broken wire in the solenoid plug at the transmission. Don't condemn the PCM before you check the wiring! You could be flushing $200 down the toilet because of a broken wire.

Broken wires like this are sometimes caused by the transmission being removed, a broken trans mount, or simply not having the wire harness in it's support clips.

My reverse light wire was broken when we lowered the trans crossmember down to give better access to the CPS.

Fracture

There aren't NSS on 4.7 transmissions unfortunately. It's apparently in a solenoid pack ABOVE the valve body.

dave1123

Yes there is and it's screwed into the side of the transmission just behind the shift cable entrance. You've got the 44re, right? If not, you're on your own and IDK what you're talking about.

Fracture

The 4.7 v8 comes with the 45RFE

Fracture

P1698 - Replaced the TCM and the code is gone. Reverse lights still out - convinced it's the solenoid pack in the transmission so I am going to just wire up a manual switch instead of taking the tranny pan off.

sdjp

I have an 02' 4.7 WJ and P1698 among a host of other codes. My reverse lights work. Main problem is the vehicle isn't starting when it's warm and sometimes no start even when cold. When I turn the key absolutely nothing happens. I can always start it by putting two wires in the starter relay holes under in the fusebox under the hood. My battery, terminals, starter, wires, are solid. I've even replaced the ignition switch and ignition actuator and saw some improvement in starting but that only lasted for a few days.

Research leads me to NSS but then as we said 4.7 doesn't have one, it's the solenoid pack and that sounds like a lot of work to do; especially when it's no guarantee. That or the PCM.

I'm all about wiring in a bypass switch. How are you going to do that?

Fracture

I don't know if the solenoid in the trans will stop it from starting yet it will jump with the wire fix you have. If I had to take a guess, it sounds like your PCM is going bad. I was having starting issues after I replaced my TCM for the P1698 code, and after getting a new PCM haven't had any starting issues since.

sdjp

Thanks, did you do the Florida company to re-flash your PCM thing, it seems that's what a lot of people do. I'm unfamiliar with what needs to be done for the PCM to be compatible.

Fracture

I went to Solopcms.com and they have a great warranty. I spent about $200 but I needed them to remove the SKIM setting which is the immobilizer unit.